Grey's Anatomy is one of the longest running medical television shows on the air. For fourteen seasons, Meredith Grey and company have won over audiences with their constant medical emergencies, devastating losses, and relationship drama.

It's one of those rare shows that spans across different generations. It's also a show with the unique opportunity to explore stories and follow characters from the beginning of their journey to where they are a decade or more later. We see Meredith as an intern, a resident, an attending, and the Chief of General Surgery — not to mention everything that happened in between. The fact that viewers still invest themselves in the show is a huge testament to its quality.

While all of these things about Grey's are great, no show is perfect. For a show that's lasted this long, the showrunners are bound to slip up a few times. Sometimes the story's continuity falls apart. Other times a character disappears without a trace. Sometimes things just don't get any explanation.

This is a problem for many television shows, and Grey's is no exception. Although the show is still going strong, it has some major plotholes that are too big to ignore.

Here are 16 Huge Grey's Anatomy Plot Holes We Can’t Unsee.

16. Derek kisses his research fellow while in Washington D.C.

Derek and Meredith — "MerDer" — is, without question, the most iconic relationship on Grey's Anatomy. Their love is undeniable, despite the challenges they went through over the years. They were devoted to one another until the very end — or, at least, Meredith was to Derek.

Meredith and Derek's relationship was somewhat on the rocks when Derek left to work in Washington D.C. to work on his brain-mapping project. While there, Derek meets Renee Collier, a talented research fellow. The two have chemistry, and share a kiss.

Yes, Derek did pull away, but he also never told Meredith about it — probably because it would have strained their relationship even more. Instead, McDreamy flies home, leaving the audience with the knowledge that he emotionally and physically cheated on Meredith, and Meredith still in the dark.

15. Arizona wins custody of Sofia, but Sofia doesn't live with her

Arizona and Callie shared an intimate bond for many seasons. That bond ultimately strengthened after Sofia's birth. After the plane crash — and Sofia's father Mark Sloan's untimely end — this relationship fell apart and resulted in a divorce.

The two entered a vicious custody battle over Sofia. They brought in their friends and colleagues to testify over who would earn sole custody. Arizona earned that right.

However, for some reason, Arizona allowed Sofia to move away with Callie and Penny — who had not been in Callie's life for that long. It doesn't make sense for Arizona and Callie to put Sofia through all of this, only for Arizona to allow Callie to take Sofia anyway. That's not how custody battles work out in real life, and it felt like needless drama on the show.

14. Meredith wins the Harper Avery

The Harper Avery is a fictional medical award given to the best of the best in the medical field. As its name suggests, the award is named after Jackson Avery's grandfather.

When Cristina earned a nomination for her cardiothoracic work, she didn't win because Grey Sloan Memorial is partially owned by the Harper Avery Foundation. However, Meredith won the award a few years later, even though she worked at the same hospital. Even though it's unfair, it makes sense that Cristina wouldn't win due to a conflict of interest.

The rules seemed to change when it was Meredith's turn.

Meredith is obviously the main character, but why start giving her preferential treatment now? The show never offers any explanation for why this is the case.

13. Where is Bailey's ex-husband?

Bailey mentions early in the series that she had been married to Tucker, her first husband, for ten years. Tucker is also the father of Bailey's son — nicknamed "Tuck."

Their marriage collapses as Bailey invests more time in her duties at the hospital, and things get even more complicated when a bookshelf falls on their son, resulting in serious injuries. Bailey and Tucker divorce, and Bailey later marries Ben Warren.

Bailey seems to be the primary caretaker for Tuck, but you'd think that Tucker would still be in his son's life. However, we never see Tucker after the events of his and Bailey's divorce, and Tucker is hardly mentioned at all.

Instead Ben becomes Tuck's father figure after he and Bailey marry. Ben is a more dynamic character anyway, but this is a plot point the showrunners never fully addressed.

12. Meredith disappears after Derek's accident, but keeps her job

Derek's ingwas devastating for Meredith. He was the love of her life, and he always will be for her. Grief presents itself in different ways, so it's completely understandable that Meredith would want to take time off from work to cope with everything.

However, Meredith takes her kids and completely drops off the grid for roughly a year — while pregnant with a third child. She offers little explanation to her colleagues to the point where Alex must track her down to make sure she's okay.

After that time jump, Meredith has her child and later returns to work with no questions asked. Maybe she's allowed to do that because she's a partial owner of the hospital, but no doctor would let her come back that easily.

11. April's values shift in a matter of seconds

April was a devout Christian who maintained a close relationship with God. For a long time, she remained abstained to honor that relationship, and held her values and beliefs very close to her.

However, the night before the residents take their medical boards, April sleeps with Jackson, which causes a dramatic shift in her character and partially causes her to fail her boards.

Characters should change with time and have their beliefs challenged by their situations, but with April, this shift happens so suddenly it's almost jarring. This moment seems to occur as a product of stress and snap-judgement rather than a thought-out decision from the character.

The way these actions unfold doesn't feel like something April would do, especially based on what we've seen from her before.

10. Andrew and Sam's relationship has little backstory

Grey's Anatomy is not known for its subtlety — sometimes to a fault. Relationships form and fall apart very quickly, and sometimes they aren't always believable.

Andrew has been an established intern and resident on the show, but his relationship with Sam, a new surgical intern, comes out of nowhere. The two share some kind of backstory, where they had a ionate on-again, off-again relationship that now follows them to Grey Sloan Memorial.

Although that much is clear, the showrunners offered zero explanation as to what really happened between them or why they know each other in the first place. It seems like they're going for a star-crossed lovers approach like with Meredith and Derek. With that huge question mark hanging over their heads, though, none of that drama feels earned.

9. Arizona's leg is barely a problem anymore

The plane crash in season nine was one of the most heartbreaking moments on Grey's Anatomy. No character who went through that experience was ever the same, including Arizona.

She severely injured her leg in the accident, and Callie made the difficult call to amputate Arizona's leg in order to save her life. Arizona resented her for this, and that moment marked the beginning of the end for their relationship.

This loss was a defining moment for Arizona's character, and her relationships with other characters.

But as significant as this event was for her, though, her leg is hardly ever brought up on the show anymore. There are moments here and there were Arizona is seen without her prosthetic, but otherwise, that gets little attention.

8. Amelia's brain tumor

Amelia may not be the most popular character on the show, but she is still a gifted neurosurgeon. She figured out how to remove Dr. Nicole Herman's brain tumor without ending her life, and she saved countless other patients. It turns out that she did this with a massive tumor in her own brain.

When the show revealed this, it seemed like Amelia might be the next character to lose her life.

A brain tumor growing inside one of the few people who could remove it had a lot of dramatic potential to it. However, surgeons removed the brain tumor with little complication, and Amelia seemed perfectly fine.

A tumor like this one would have greater effects on the patient, but Amelia recovered very quickly and there don't seem to be any lasting effects on her behavior or personality. It feels ignorant to dismiss that huge event so suddenly.

7. Arizona switches specialties

Becoming a doctor is no easy task. There are years of medical school and residency before you can become an attending and specialize in a field.

Arizona was the Head of Pediatric Surgery in the hospital, but over the course of a few episodes, she also becomes a specialist in fetal surgery. Then she takes over that department for Nicole Herman after she loses her eyesight in surgery.

Arizona is a good surgeon and all, but there's no way she could learn the necessary skill set and take over a whole new department that quickly. Was there seriously no one that the hospital could have brought in as an attending for fetal surgery?

Arizona spent most of her career in pediatrics, but transitioned to a new specialty without any major roadblocks.

That feels like a misguided attempt to change things up for the character.